I'll start:

Warlock - you can no longer create a soul stone while in combat, you can use on, but not create. Need to try Healthstones to see if you can still make those along with trying to make a soulwell.

Priest - You can no longer cast Prayer of Mending on a non-group/raid member (Bolty found this last night)

The Mana per 5 bug appears to be fixed. My testing showed the amount of mana regen I was actually receiving matched the amount shown in the character screen.

I was unable to do this even before the patch. I was under the impression that because it hops among party/raidmates, that it could only be cast on party/raidmates (like PW:Shield).